Repairing power tools all the time, you can’t avoid using a spot welder; there is low power, high power, extra-high power, and this one counts as medium. Low power suits people who don’t use one often and only occasionally build two or three or four or five cells — a few times a month at most, buy the small type, a hundred-odd yuan, switch it on and click away, very handy, on and off as needed. The medium type means opening the box, taking out the main unit and hooking up the leads before welding, also handy, a bit more power. High power suits people who build their own Li-ion packs all the time for fun, also very good. Watch safety with Li-ion: two or three cells don’t matter, doing them in bulk is a little risky, especially while charging. Not often, occasional use: buy the small one; using it all month: buy medium or high power — what suits you matters. I have small, medium and large, but I use the small one by far the most, two or three times a month, sometimes not even once; I like the small one, grab it and go. 2 comments: ‘AWithZ Li-ion spot welders suit individuals / small repair shops, industry-leading, good materials, no corner-cutting, miles ahead of the rest’ (sounds like official / promotional copy).